ABSTRACT
This chapter discusses the special theoretical techniques performed recently to overcome and obey multiscattering and multidiffraction effects caused by the environment of a signal reflected or passing through the object under investigation buried in the sub-surface media or embedded and hidden in different material structures. It presents the non-linear approach of diffraction tomography based on Feynman's path integral evaluation, which allows us to obtain better imaging of the shape and dimensions of any foreign object embedded in clutter conditions. The wave field formed as the result of the focusing procedure at the plane of focusing has the form of quasi-parallel (collimated) beams of electromagnetic radiation. The operation of focusing is based on the in-phase summation of complex amplitudes of the scattered wave field and on the selection of the point of focus. In some practical applications, the two-step focusing procedure would be not so precise, namely, in a multilayered medium, or even in a homogeneous regular environment.
